• Basic Information
• Additional Info

Basic Information

• Project No. and Title: W4128 : Microirrigation: A Sustainable Technology for Crop Intensification and Improved Crop Productivity
• Period Covered: 10/01/2018 to 09/30/2019
• Date of Report: 12/09/2019
• Annual Meeting Dates: 11/10/2019 to 11/10/2019

Participants

Davie Kadyampakeni (dkadyampakeni@ufl.edu) University of Florida, Ripendra Awal (riawal@pvamu.edu) – Prairie View A&M University; Freddie Lamm (flamm@ksu.edu) – Kansas State University (Zoom), Saleh Taghvaeian (saleh.taghvaeian@okstate.edu) - Oklahoma State University (Zoom); Clinton Shock (Clinton.shock@oregonstate.edu) Oregon state University; Manoj K. Shukla (shuklamk@nmsu.edu) New Mexico State University; Pete Jacoby (jacoby@wsu.edu) - Washington State University; Jirka Simunek (jsimunek@ucr.edu) University of California Riverside; Howard Neibling (hneiblin@uidaho.edu) - University of Idaho (Zoom); Kenneth Shackel (kashackel@ucdavis.edu) - University of California Davis, Dana Porter (dporter@ag.tamu.edu) Texas A & M university (Zoom); Naftali Lazarovitch (lazarovi@bgu.ac.il) BenGurion University; Bipul K. Biswas (biswasb@fvsu.edu) Fort Valley State University

Accomplishments

Impacts

1. The HYDRUS models are being constantly updated based on research carried out by the W3188 group. The HYDRUS 1D model was downloaded more than ten thousand times in 2019 and over forty thousand HYDRUS users from all over the world registered at the HYDRUS website. We continue supporting all these HYDRUS users from USA and around the world at the HYDRUS website using various tools, such as Discussion forums, FAQ sections, and by continuously updating and expanding a library of HYDRUS projects.
2. We have added new capabilities to rigorously consider processes in the soil profiles with furrows (the Furrow module), to calculate cosmic ray neutron fluxes (the Cosmic module) and to simulate the translocation and transformation of chemicals in the soil plant continuum (A Dynamic Plant Uptake module).
3. Iin 2019 we have offered short courses on how to use HYDRUS models at a) Czech University of Life Sciences, Prague, Czech Republic, b) Colorado School of Mines, Golden, CO, c) Indian Institute of Technology (IIT) Mandi, Mandi, Himachal Pradesh, India, and d) the Sede Boker Campus of the Ben Gurion university, Israel. About 100 students participated in the short courses.
4. Continued adoption of subsurface drip irrigation (SDI) has occurred in Kansas and neighboring Great Plains states with a five-year increase in land area of 18, 82, and 17 percent for Kansas, Nebraska, and Texas, respectively according to USDA-NASS data.
5. SDI system longevity of greater than 25 years was demonstrated by a system at KSU-NWREC.
6. SDI economics fluctuate considerably with crop prices and KSU has annually provided an updated template to compare SDI to center pivot sprinkler irrigation.
7. Simplified equations to size SDI flushlines were developed enabling designers to determine sizes more easily.
8. A decision support system for variable rate irrigation (VRI) center pivot systems developed by scientists at the USDA ARS Conservation & Production Research Laboratory, Bushland, TX, was beta tested from 2016 through 2019 in Texas, Mississippi, Missouri, Nebraska and South Carolina. The patented system (U.S. Patent No. 8,924,031) is embodied in a client-server software system named ARSPivot and associated wireless plant canopy temperature, soil water content and weather sensors that constitute the Irrigation Scheduling Supervisory Control And Data Acquisition (ISSCADA) system. Beta testing has been accomplished in conjunction with a Cooperative Research And Development Agreement (CRADA) with Valmont Industries. Development of the plant feedback part of the system began in 1995 with infrared thermometers and a control system that logged canopy temperatures and made automatic decisions to control valves to irrigate corn and soybean using surface and subsurface drip irrigation. The system was converted to center pivot sprinkler irrigation systems beginning in 2004 and has been used successfully to automatically schedule irrigation of corn, cotton, potato, sorghum and soybean. It remains useful for microirrigation scheduling. Success is defined by obtaining yields and water use efficiencies as large as or larger than those obtained using irrigation scheduling based on weekly neutron probe readings throughout the root zone. Since the neutron probe is the most accurate system for irrigation scheduling based on soil water content, success of the ISSCADA system meets a very high bar. The patent has been licensed for commercialization by Valmont Industries, Inc.
9. Soil water sensing can be effective for irrigation scheduling only if the data are available to the farmer easily and with a minimum of labor. A team of scientists and engineers from the USDA ARS at Bushland, TX, and at Beltsville, MD, worked with Acclima, Inc. through a Cooperative Research And Development Agreement (CRADA) to develop and make commercially available a node and gateway system for automatic, unattended wireless transmission of soil water sensor data from the field to the Internet Cloud. USDA ARS at Bushland has developed an app that allows a user to easily download the data from the Cloud. The system is manufactured for USDA ARS and used from Alaska to the Southeastern USA as well as in Jordan and Uzbekistan. A fully commercial system is expected to be for sale at the end of the first quarter 2020.
10. Irrigation application method can impact crop water use and water use efficiency, but the mechanisms involved are incompletely understood, particularly in terms of the water and energy balances during the growing season from pre-irrigation through planting, early growth and yield development stages. Grain corn (Zea mays L.) and sorghum (Sorghum bicolor L. Moench) were grown on four large weighing lysimeters at Bushland, Texas in 2013 (corn), 2014 and 2015 (sorghum) and 2016 (corn). Two of the lysimeters and surrounding fields were irrigated by subsurface drip irrigation (SDI) and the other two were irrigated by mid elevation spray application (MESA). Crop evapotranspiration was determined using both the weighing lysimeters and by soil water balance in eight locations in each field with soil water contents measured using the neutron probe. Final biomass and yield were measured. Irrigation amounts were metered and also measured by lysimeter mass balance. Compared with MESA irrigation, using SDI saved 48 mm (based on NP for DOY 170-189, 85 based on Lys) and 53 mm of water that was lost to evaporation early in the season (1st pre-plant irrigation to 25 days after planting, DAP) in 2013 and 2014, respectively, and 59 mm (110 based on Lys) and 112 mm for the 2013 and 2014 seasons, respectively. In the wetter 2015 and 2016 seasons, using SDI saved 11 and 12 mm, respectively, through 25 DAP, and 50 and 139 mm total for the season, respectively. While sorghum, particularly short season sorghum, is not a crop ordinarily considered for SDI, it was grown successfully using SDI with yields averaging 6.48 and 7.53 Mg ha 1 in 2014 and 2015, respectively, comparable to others reported for short season sorghum at Bushland. In the relatively dry 2013 season, SDI reduced overall corn water use by 59 mm while increasing yields by 1.88 Mg ha-1 (20%) and WUE by 0.64 kg m-3 (61%) compared with MESA full irrigation. In the relatively wet 2016 season, SDI reduced corn water use by 139 mm and increased WUE significantly, but with insignificant difference in yield between SDI and MESA irrigation methods. Significant and relatively large differences in water use indicate that crop coefficients should be tailored specifically for SDI management, and that crop coefficients determined using sprinkler irrigation are likely to be too large and lead to over irrigation if used to scheduled SDI.
11. Declining quantity and quality of water resources in the region are driving adoption of efficient irrigation technology and demand for information resources. Microirrigation (mostly subsurface drip irrigation) is relatively widely used in the Texas High Plains, where affected land area is approaching an estimated well over 500,000 acres (increase from an estimated 20,000 acres statewide in 2000 to estimated 700,000 statewide in 2019). Most of this land area is under cotton production, but agronomic seed production, declining water resources, cost-share programs and a growing winegrape industry also are contributing significantly to this growth in adoption of microirrigation and sensor-based / weather-based irrigation management.
12. UC-Davis' greatest impact is in the development of precision irrigation management systems for specialty crops. For example, our site specific irrigation of almonds project through retrofitting of microirrigation systems has attracted a lot of attention from the growers (printed in two grower oriented magazines) and also received funding from the almond board of California. Our work on high frequency fertigation is also expected to reduce nitrate leaching which is a serious problem in the central valley of California but also improve yields. The web based iCrop decision support system has attracted a lot of interests from growers and crop consultants and is expected to help growers optimize yields and inputs in good years (wet years) while minimizing inputs in bad years (extreme drought) to optimize overall net profitability.
13. Lack of in-season grower willingness to input irrigation data limited the usefulness of the water budget approach. When actual soils, crop and irrigation information was entered into the WSU scheduler, results (indicating when and how much the grower should irrigate, and amount of deep percolation loss) compared well with the soil sensor method. Because the WSU scheduler is free for grower use, development of a method to integrate actual irrigation information into the scheduler (the major barrier to adoption) should significantly increase the level of grower adoption, and result in better utilization of limited irrigation water.
14. Because of the improved sensor soil water measurements this year, growers were more confident in trusting the results, and 1 of the 3 growers shut off the LESA pivot based on sensor data. Due to ample early-season irrigation, the pivots on the Rexburg bench site did not require irrigation until July 5. After that time, the Control pivot ran continuously and still fell behind with the soil profile drying to water stress levels below 18 inches by mid-season and all sensors indicating water stress by the end of the season. In contrast, based on sensor readings,19% less water (one less irrigation) was applied to the LESA pivot, and soil water content at all depths remained at non-stressed levels throughout the entire season. Grain yield and quality were equal on both pivots, but the use of sensors to shut off the LESA pivot when needed resulted in energy savings of 6300 kWh or a cost savings of approximately $500 per irrigation.
15. Use of either of these approaches will probably increase in coming years due to the requirement that water application on approximately 1 million acres of farm land irrigated from ground water sources be reduced by 10-15% in response to settlement of a long-standing lawsuit between the Surface Water Coalition and participating members of the Idaho Ground Water Appropriators, Inc. Requirements for pumping reduction along with the requirement for IDWR approved flow meter installation were mostly implemented in 2018 and will be fully implemented in 2019. Based on results of a number of Pacific Northwest irrigation scheduling studies, use of either the web-based scheduling approach or the soil water sensor approach can play a major role in meeting the requirements of the settlement.
16. Usage of subsurface drip irrigation (SDI) continues to grow in the USA even with lower commodity prices. Interest in the technology has continued to grow internationally for a variety of crops.
17. Initial results from a field study with SDI has indicated that corn grain yields and crop water productivity can be increased with cropping intensification without increasing irrigation.
18. Saline groundwater is increasingly used for irrigation in New Mexico and salinity induced abiotic stresses and quantification of the salinity induced influences on physiology, growth, and yield of chile and Pecans are important for the sustainability of agriculture in New Mexico. The strategy of growing glycophytes and halophytes under a water salinity gradient will be useful for food security mission of USDA. These experiments and results demonstrates that continuous long-term use of brackish water can increase soil salinization and decrease chile pepper yields.
19. Declining quantity and quality of water resources in the region are driving adoption of efficient irrigation technology and demand for information resources. Microirrigation (mostly subsurface drip irrigation) is relatively widely used in the Texas High Plains, where affected land area is approaching an estimated 500,000 acres (increase from an estimated 20,000 acres statewide in 2000). Most of this land area is under cotton production, but agronomic seed production, declining water resources, cost-share programs and a growing winegrape industry also are contributing significantly to this growth in adoption of microirrigation and sensor-based / weather-based irrigation management.

Publications